Mono Crystalline

better the Poly-Crystalline Solar Panel or MONO-CRYSTALLINE?

The monocrystalline panels have slightly higher theoretical efficiencies than the polycrystalline panels. However in practice there is often little difference between the two, and sometimes mono panels have lower efficiency than poly panels.

There is usually a small price premium for mono-panels, and they also use more active materials in their manufacture, so you could even argue they are "less green" than poly panels!

Otherwise their performance is very similar in terms of output for various radiation levels, expected service life etc.

So overall it could be argued that poly panels are slightly better, but at the end of the day it depends which factors are most important to you.